Wireless communication systems often comprise a group of subscribers and a set of stationary “base radios” or “base stations” (also known as “repeaters”). The subscribers are typically endpoints of a communication path over a channel resource, (e.g., a voice channel) of the wireless communication system, wherein the repeaters are typically the intermediaries by which the communication path to a subscriber may be established or maintained. There are often many simultaneous communications taking place in the wireless communication system. Groups of users that may use a shared communication system can be affiliated within specific talk groups which may exclude other users of the communication system. In this way, users within a common talk group can communicate between themselves without their communications being available to everyone who happens to have access to a shared communication system. Therefore, a talkgroup call allows a user of one subscriber to speak while several other affiliated subscribers listen. The group of subscribers participating in the call are corporately called the talkgroup. Because there are often many simultaneous communications taking place in the wireless communication system, a user may wish to participate in one talkgroup call while monitoring other communications such as may occur in other talkgroup calls.
Direct mode operation (DMO) is a communication technique where a radio can communicate with one or more other radios without the need for additional infrastructure equipment (e.g. base stations or repeaters). Thus direct mode operation can provide a more efficient, less costly communication system than repeater mode operation, although the DMO means of commutation may afford less coverage range due to the reduced power of the hand held portable as compared to the base station. Further, the use of direct mode operation that supports talkgroup affiliation, while providing efficient communication of the DMO operational parameters is therefore desirable so as to provide for optimal data throughout and power efficiency
Accordingly, there is a need for an improved method and system for direct mode communication within a talkgroup.
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The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.